Removable wear bushing for cylinders



March 17, 1925.

R.A.NORUNG REMOVABLE WEAR BUSHING FOR CYLINDERS Filed Dec. 18, 1922 Patented Mar. 17, 1925. I

UNITED STATES PATENT OFFICE.

'BEINEQLI') A. NORLING, or AURQRA, ILLINOIS, ASSIGN-OR- 'ro INDEPENDENT PNEU- MA'.I.IC TOOL COMPANY, or CHICAGO, ILLINQIs. a conronA'rIoN or DELAWARE.

REMOVABLE WEAR BUSHING FOR CYLINDERS.

Application filed December 18, 1922. Serial No. 607,619.

This invention relates to removable Wear bushings for cylinders in which pistons or like parts have movement.

'journaled t erein and by The invention has particular reference to cylinders of portable pneumatic-drills, and

has for its main object to provide novel means for removably holding the bushings in the cylinders of such tools so that the life and usefulness of, the latter may be prolon ed by being able to readily replace worn bu ings by new ones.

In the accompanying drawing Fig. 1 is a cross-sectional view through a pneumatic drill, the power cylinders of which are provided with removable wear bushings of my invention;

Fig. 2 is a top plan view taken on line 22 of Fig. 1; and

Fig. 3 is a erspective view of one of the removable bus ings.

In the drawings, 1 indicates the outside casing of a neumatic drill, 2the crank shaft which the drill (gnot shown) is turned, 3, 3 the power cylin ers on opposite sides of the crank shaft and at angles thereto 4 the pistons reciprocating in said cylinders, and 5 the connecting rods connecting the pistons with the crank shaft.

Each cylinder 3 is lined with a removable wear bushin 6 having the length of the cylinder or aingth covering the entire stroke of the piston 4, and an inside diameter conforming to the outside diameter of the piston 4. The cylinder 3 has an inside diameter large enough to receive the bushin 6.

daid bushing 6 is made of metal having suitable wear resistin properties, such as required in tools of t is character, and is provided at its outer end with outwardly extending lugs 7, 7. These, as shown in the drawings, are diametrically arran ed and seat in recesses 8, 8 provided in t e outer end of the cylinder 3. The outer end of the cylinder'is open to allow the bushing 6 to be pressed into the same, and the lugs 7, 7

spindle seating in the recesses 8, 8 limit the movement of the bushing into the cylinder. Said lu 's also hold the bushing against turning.

The lugs 7 and recesses 8 are of such dimensions that the outer end of the bushing 6 is flush with the correspondin end of the cylinder 3, and are held in sai recesses by a cap late 9. This is bolted or otherwise secure over the outer end of the cylinder 3 and closes the same and seats against the lugs 7, 7 to hold the bushing 6 in place and against outward movement. A gasket or packing 10 is between the plate 9 and the cylinder 3 to prevent leakage.

As shown in Fig. 2, two cylinders 3 are in a cylinder block 11 and two are on each side of the crankshaft with the bore 12 for the controlling valve 13 between them. This valve is reciprocated by an eccentric 14 on the crank shaft 2 (Fig. 1). The valve bore or cylinder 12 is lined with a wear bushing 15. This bushing has its outer end flush with the open outer end of its cylinder 12 and is held in place by the cap plate 7. The latter extends over both power cylinders 3 and the valve cylinder 12.

The valve 13 controls the supply and exhaust of compressed air or other motive fluid to and from the power cylinders 3 on opposite sides of it, and in this connection each bushing 6 has a number of ports .16, 16 on one side and adjacent its upper end, as shown-in Fi 3.

As shown in igs. 1 and 2, the recesses 8, 8 are slightly longer than the lugs 7, 7 to ermit a screw driver or other implement to e inserted under the lugs for lifting a bushin 6 from its cylinder from its outer end. he lugs 7 in holding the bushings a ainst turning hold the ports 16 therein a ways in register with those in the cylinder block 11.

The power cylinders 3 3 wear out the quickest in tools of the kind herein mentioned, and by the use of removable wear bushings 6, 6 the life and usefulness of the tools may be prolonged by replacing, from time to time, worn bushings 6 by new ones.

I claim as my invention:

1. In combination with a cylinder block having two power cylinders and an interosed valve cylinder therein, all-of said cylmders having their outer ends opening through the same end of said block, a wear bushing in each of said power and valve cylinders, the bushings in the; power cylinders having outwardly projectin lugs seating in recesses in the cylinder hock, and a N single cap plate secured to the block over the power and valve cylinders'for closing the same and enga in "the outer-endsjofw said bushings and e ugs .for holding the bushings in their respective c linders.

2. Incombinatioh with a cy inder, a. wear bushing lining the inner wall of the cylinder and being removably inserted through the open outer end thereof, said bushing having lugs at its outer end and seating 1,029,911 a i I in recesses in the outer end of the c linder, and a cap plate secured to theicylin er over the outer end thereof and engaging said lugs for clamping the same in said recesses and holding the bushing in said cylinder, said recesses being longer than said lugs to allow for lifting the bushing out of the cylinder from the outer end thereof.

In testimony that I claim the foregoing as my invention, I 'afiix my signature, this 12th day of Dec., A. D. 1922.

- REINHOLD A. NORLING. 

